Sulfuric Acid → 4-Cyclopropyl-2-fluoro-1-iodobenzene

Participants

Reaction Steps

To a stirred mixture of 4-cyclopropyl-2-fluoroaniline (1.63 g, 10.78 mmol) in water (20 mL) at 0° C. was added concentrated sulfuric acid (8.6 mL, 15.0 eq.) dropwise, while keeping the temperature constant at 0° C. A solution of sodium nitrite (781.0 mg, 11.32 mmol, 1.05 eq.) in water (2.7 mL) was added and stirred for 5 minutes. This resulting reaction mixture was then added to a solution of potassium iodide (3.76 g, 22.64 mmol, 2.1 eq.) in water (9.7 mL), and the reaction mixture was stirred at 60° C. for 3 h. DCM (400 mL) was added to the cooled reaction. The biphasic layers were separated, and the aqueous layer was extracted with DCM (2×150 mL). The combined organic layers were washed with saturated aqueous Na2S2O4, water, and brine, dried over Na2SO4, filtered, and concentrated under reduced pressure. The crude residue was purified via flash column chromatography eluted with 100% heptane to give 2.01 g (71.28%) of 4-cyclopropyl-2-fluoro-1-iodobenzene as a clear oil. 1H NMR (400 MHz, CDCl3) δ 7.57 (dd, J=8.0, 6.9 Hz, 1H), 6.76 (dd, J=9.4, 1.9 Hz, 1H), 6.64 (dd, J=8.2, 1.9 Hz, 1H), 1.94-1.77 (m, 1H), 1.09-0.95 (m, 2H), 0.79-0.56 (m, 2H).

Provenance & Evidence